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Table 2

Center-to-limb variation of the convective shifts.

Spectral line Heliocentric parameter μ = cos Ө


Element λ0 (Å) Part 1.0 0.95 0.9 0.85 0.8 0.7 0.6 0.5 0.4 0.3
Fe I 6301.5008 Line core − 107 − 74 − 81 − 99 − 82 − 101 − 64 − 18 + 33 + 85
Mean bis. − 295 − 244 − 251 − 269 − 246 − 271 − 255 − 206 − 156 − 87
Synthesis − 307 − 349 − 358 − 351 − 325 − 279 − 211 − 101
Fe I 6302.4932 Line core − 164 − 139 − 163 − 195 − 178 − 204 − 173 − 115 − 47 + 33
Mean bis. − 295 − 249 − 262 − 281 − 260 − 286 − 274 − 221 − 170 − 94
Synthesis − 335 − 387 − 404 − 403 − 381 − 342 − 280 − 176
Fe I 6303.460 Line core − 420 − 398 − 394 − 423 − 392 − 434 − 420 − 385 − 359 − 277
Mean bis. − 422 − 388 − 390 − 419 − 381 − 444 − 455 − 417 − 402 − 347
O I 6300.304 Line core +272 +327 +306 +265 +263 +224 +232 +221 +201 +235
Mean bis. + 214 + 262 + 241 + 201 + 232 + 169 + 142 + 161 + 163 + 191
Sc II 6300.6795 Line core − 387 − 316 − 351 − 372 − 338 − 382 − 387 − 355 − 294 − 241
Mean bis. − 344 − 288 − 312 − 339 − 298 − 357 − 366 − 332 − 304 − 257
Si I 6299.590 Line core − 253 − 223 − 253 − 296 − 277 − 334 − 328 − 269 − 185 − 48
Mean bis. − 484 − 460 − 485 − 515 − 482 − 534 − 530 − 467 − 385 − 259
Ti I 6303.7565 Line core − 353 − 317 − 331 − 366 − 335 − 380 − 379 − 342 − 296 − 225
Mean bis. − 347 − 304 − 325 − 354 − 320 − 379 − 395 − 353 − 324 − 277

Notes. The Doppler velocities (in m s−1) were obtained either from the line core position or the mean bisector. The heliocentric parameter μ is the cosine of the heliocentric angle θ, ordered from the disk center (μ = 1.0) to the solar limb (μ = 0.3). Line core velocity was determined by a parabolic fit to the intensities around the line minimum. The mean bisector is the average of all bisector centers from the line core to the spectral continuum. For the deeper lines Fe i 6301.5 Å, 6302.5 Å, and Si i 6299.6 Å the upper threshold was set to 95% of the continuum intensity. The values of the synthesis (same threshold region) were taken from Table 2 of de la Cruz Rodríguez et al. (2011). For the weaker lines Fe i 6303.5 Å, O i 6300.3 Å, Sc ii 6300.7 Å, and Ti i 6303.8 Å, the upper intensity level was defined as 98%.

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